Repeating Cusor-character Prevents Windows 8 Logon on Pavilion G7

HP Pavilion G7 laptop running Windows 8



The problem seems to accompany the heated-up computer. If I restart quickly, the problem keeps me from loging in to Windows because I can't enter the password.



The cursor repeats some character continually and doesn't stop. It may be a character from a pressed key or the character may come up on its own. If there's a field of document that will accept keyboard input, I'll get something like ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| and so on forever.



If I restart and allow the computer to cool while off, I can logon to Windows normally, but after a while, the behavior will start.



(I tied removing the wireless mouse transmitter. No change.)

 

Since the problem seemed heat related, I vacuumed backwards through the air intake on the laptop. So far, things are working normally.